Sulphur dyestuffs from dihydroindole-indophenolic bodies



Patented Aug. 20, 1929.

11,725,046 UNITED STATES PATENT OFFICE.

riurz BALLA-UF, or ELBEBFELD, GERMANY, ASSIGNOR "10 GENERAL amnnm woaxs,

' INC 01" NEW YORK, N. Y., A

CORPORATION OF DELAWARE.

SULPHUR nxns'rurrs r3011: nmvnnomnowrmnornmomo :BoDma Io Drawing. Application filed October 25, 1926, Serial No. 144,187, and in .Germany November 2, 1925.

The resent invention relates to sulphurv dyestu s dyeing violet to blue shades which are obtained when acting with sulphur upon dihydroindole-indopl1enolic bodies.

I havedescribed in my co-pending application Serial N 0. 144,188, filed on even date, that dihydroindole's having the general formula R N 121 onn \CH/R wherein R stands for hydrogen or an alkyl, aralkyl or aryl group, R stands for a ben zene nucleus whichmay be substitutedby an alkyl, aryl, aralkyl, halogen or any other monovalent group, will produce indophenolic bodies when submitted to the usual react-ions leading to the formation of indophenols. These indophenols form deep red to blue colored alkaline solutions, which are easily reduced to the corresponding lcuco-indophenols which are yellow colored crystalline substances, easily soluble in water, alcohol and sulfuric acid. The alkaline solutions of the leuco-indophenols are easily oxydized, for instance by action of atmospheric oxygen, to the corresponding indophenols. The leuco-indophenols have most probably the formula I R N nl\ one C4,

I have now found that by submitting these novel dihydroindole-indophenols v or their leuco derivatives toa sulphur fusion novel let to light and .boiling.

prefer, however, phide fusion.

My novel sulphur dyestuffs are dark vioblue powders, they are soluble in sodium sulphide solutions, from which cotton is dyed violet to blue shades exceedingly fast to light and boiling. They can also be reduced to. form vats, from which cotton is dyed similar shades.

The following examples will further illus, trate my invention, the parts being by weight:

to use an alcoholicpolysul- Example 1-22 parts 2 -phe'nyl-dihydroindole-5-p-leuco-indophenol of the formula are added to a polysulphide consisting of about 400 parts alcohol, 95 parts calcined sodium sulphide and. 11-7 parts sulphur. The melt is then heated to 170 C. for about 100 hours; the alcohol is then under addition of water and the aqueous melt filtered off. The excess sulphur is then extracted from the either by means of the correct figured out amount of sodium sulphide. The residue is well washed, filtered and dried. It is a bluish-violet powder which dyes cottonfrom a sodium sulphide bath violet shades- \Ewample 2.17;5 parts 2-methyl-dihydroindo1e-5-p-leuco-indophenol formula is subjected to an alcoholic polysulphide fusion as described in Example 1. The dyestuff obtained is a violet ton from a sodium sulphide bath a dull urple shade of good fastness to light and iling. 1

Example 3.By submitting 1-2-dimethyl;

crude product obtained, a solvent for sulphur, or

of excellent fastness to" of the probable distilled off powder, it dyes cot- I wherein R stands for hydrogen, an alkyl,

dihydroindole-S-pdeucoindopheriol of the probable formula ..N xxx-cm chi leg to -'an alcoholic polysulphide melt as described in Example 1, a sulphur dyatufl' is obtained as a blue powder which dyes cotton indole-indophenolic' body which in form of its leuco derivative has most probably the formula n for hydrogen, an alkyl, aryl or aralkyl group. R stands for a henzene nucleus which may be substituted by an alkyl aryl, aralkyl, halo or other monovalent up to a polysulp e fusion.

2. e rocess of producing a sulphur color which comprises submitting a dihydroindole-indophenolic body which in form of itsleuco-derivative has mostprobably the J p wherein R stands for hydrogen, an alkyl,

formula e m a uryljor laralkyl group to a polysulphide fusion.

13. The prom of producing sulphur color which comprises submitting a dihydroindole-indophenolic body,-

in formof 1 most probably the its leuco derivative has formula: I

wherein ,R stands for alkyl, aryl, or aralkyl group to a polysulphide fusion.

4. The process of producing a sulphur .color which comprises treating 2-phenvl-dir hydroindole 5 p leucoindophenol' of the probable formula at about 170 C. with an alcoholic polysulphide fusion, in which the polysulphide corresponds about to the formula m s 5. As new products sulphur dyestuffs which in the dry state are violet to blue powders, dyeing cotton from a sodium sulphide bath violet to blue shades, particularly fast to light and boiling and which are substantially identical with the products obtained by; -submitting dihydroindole-indm phenolic bodies, which inthe form of their leuco-derivatives have mostprobably the formula phide bath vio et to blue shades, larly fast to light and an which articuare substantially identical with the products obtained by submitting dihydroindole-indophenolic bodies, which in .the fonn of their the formula:

leuco derivatives have most probably aralkyl' gmup to a. polysulphide fusion.

7. As a new roduct the sulphur dyestufi ,at about 170 C. with an alcoholic polysulwhich in the ry state is a v olet powder, phide in which the polysul hide corresponds dyeing cotton from a sodium sulphide bath about to the formula Na and extracting 1 violet shades of excellent fastness to light the excess sulphur from the crude dyestuff 5 and boiling and which is substantially idenobtained.

tical with the roduct obtained by treating In testimony whereof, I aflix m signature. 2-phenyl dihydioindole-5 p-leucoindophenol FRITZ BAiLAUF. 

